.mailmap

@@ -72,3 +72,9 @@ Zhang Ning <zhangning737@gmail.com> Rooney <43574869+zhangning737@users.noreply.
 Zhang Ning <zhangning737@gmail.com> zhangning737 <zhangning737@gmail.com>
 dependabot[bot] <no-email> dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
 dependabot[bot] <no-email> dependabot[bot] <dependabot[bot]@users.noreply.github.com>
+Robert Habel <Robert.Habel@student.tu-freiberg.de> Robert Habel <robert.habel@student.tu-freiberg.de>
+Linda Günther <linda.guenther@student.tu-freiberg.de> Linda Günther <Linda.Guenther@student.tu-freiberg.de>
+Sophia Einspänner <sophia.einspaenner@student.tu-freiberg.de> Sophia Einspänner <Sophia.Einspaenner@student.tu-freiberg.de>
+Jakob Randow <jakob.randow@web.de> jrandow <jakob.randow@htwk-leipzig.de>
+Jakob Randow <jakob.randow@web.de> jrandow <jakob.randow@web.de>
+Olaf Kolditz <olaf.kolditz@ufz.de>

.vale.ini

@@ -10,9 +10,9 @@ Packages = Hugo
 BasedOnStyles = Vale, write-good, ogs
 Vale.Spelling = None
 write-good.ThereIs = suggestion
-write-good.Passive = suggestion
-write-good.TooWordy = suggestion
-write-good.Weasel = suggestion
+write-good.Passive = None
+write-good.TooWordy = None
+write-good.Weasel = None
 write-good.E-Prime = None
 
 TokenIgnores = \

CITATION.cff

@@ -10,8 +10,11 @@ license: BSD-3-Clause
 doi: 10.5281/zenodo.591265
 # The following needs to be adapted on releases:
 version: "6.4.3"
-date-released: "2022-04-01"
+date-released: "2022-09-19"
 identifiers:
+    - type: doi
+      description: "Zenodo DOI for 6.4.3"
+      value: 10.5281/zenodo.7092676
     - type: doi
       description: "Zenodo DOI for 6.4.2"
       value: 10.5281/zenodo.6405711

ProcessLib/BoundaryConditionAndSourceTerm/RobinBoundaryConditionLocalAssembler.h

@@ -47,16 +47,23 @@ public:
     {
     }
 
-    // TODO also implement derivative for Jacobian in Newton scheme.
     void assemble(std::size_t const id,
                   NumLib::LocalToGlobalIndexMap const& dof_table_boundary,
-                  double const t, std::vector<GlobalVector*> const& /*x*/,
-                  int const /*process_id*/, GlobalMatrix& K, GlobalVector& b,
-                  GlobalMatrix* /*Jac*/) override
+                  double const t, std::vector<GlobalVector*> const& xs,
+                  int const process_id, GlobalMatrix& K, GlobalVector& b,
+                  GlobalMatrix* Jac) override
     {
         _local_K.setZero();
         _local_rhs.setZero();
 
+        auto& x = *xs[process_id];
+
+        auto const indices = NumLib::getIndices(id, dof_table_boundary);
+        auto const local_x = x.get(indices);
+        auto const u =
+            MathLib::toVector<Eigen::Matrix<double, ShapeFunction::NPOINTS, 1>>(
+                local_x, ShapeFunction::NPOINTS);
+
         unsigned const n_integration_points =
             Base::_integration_method.getNumberOfPoints();
 
@@ -86,19 +93,35 @@ public:
                 integral_measure = (*_data.integral_measure)(t, position)[0];
             }
 
-            // flux = alpha * ( u_0 - u )
-            // adding a alpha term to the diagonal of the stiffness matrix
-            // and a alpha * u_0 term to the rhs vector
-            _local_K.diagonal().noalias() +=
-                N * alpha.dot(N) * w * integral_measure;
-            _local_rhs.noalias() +=
-                N * alpha.dot(N) * u_0.dot(N) * w * integral_measure;
+            double const a = alpha.dot(N) * w * integral_measure;
+
+            // The local K matrix is used for both, the Newton and Picard
+            // methods.
+            _local_K.noalias() += N.transpose() * N * a;
+
+            if (Jac != nullptr)
+            {
+                _local_rhs.noalias() -= N.transpose() * (u - u_0).dot(N) * a;
+            }
+            else
+            {
+                _local_rhs.noalias() += N.transpose() * (u_0.dot(N) * a);
+            }
         }
 
-        auto const indices = NumLib::getIndices(id, dof_table_boundary);
-        K.add(NumLib::LocalToGlobalIndexMap::RowColumnIndices(indices, indices),
-              _local_K);
         b.add(indices, _local_rhs);
+        if (Jac != nullptr)
+        {
+            Jac->add(NumLib::LocalToGlobalIndexMap::RowColumnIndices(indices,
+                                                                     indices),
+                     _local_K);
+        }
+        else
+        {
+            K.add(NumLib::LocalToGlobalIndexMap::RowColumnIndices(indices,
+                                                                  indices),
+                  _local_K);
+        }
     }
 
 private:

ProcessLib/HeatConduction/Tests.cmake

@@ -2,6 +2,8 @@ if (NOT OGS_USE_MPI)
     OgsTest(PROJECTFILE Parabolic/T/1D_freezing_column_Stefan/Stefan_problem.prj RUNTIME 2)
     OgsTest(PROJECTFILE Parabolic/T/1D_freezing_column_Stefan/Stefan_problem_homogen.prj RUNTIME 1)
     OgsTest(PROJECTFILE Parabolic/T/2D_freezing_disk/circle_disk.prj RUNTIME 2)
+    OgsTest(PROJECTFILE Parabolic/T/2D_Robin/square_1e4_robin.prj RUNTIME 1)
+    OgsTest(PROJECTFILE Parabolic/T/2D_Robin/square_1e4_robin_newton.xml RUNTIME 1)
 endif()
 
 AddTest(
@@ -128,25 +130,31 @@ AddTest(
     REQUIREMENTS OGS_USE_MPI
 )
 # SQUARE 1x1 HEAT CONDUCTION TEST -- AXIALLY SYMMETRIC
-# test results are compared to 3D simulation on a wedge-shaped domain
+# The results were compared to an analytical solution (method of manufactured
+# solutions). The vtkdiff comparison is against the numerical solution.
 AddTest(
-        NAME 2D_HeatConduction_axi
-        PATH Parabolic/T/2D_axially_symmetric
-        EXECUTABLE ogs
-        EXECUTABLE_ARGS square_1e2_axi.prj
-        TESTER vtkdiff
-        DIFF_DATA
-        wedge_1e2_axi_ang_0.02_t_2s_extracted_surface.vtu square_1e2_axi_ts_2_t_2.000000.vtu temperature temperature 1.7e-5 1e-5
-        wedge_1e2_axi_ang_0.02_t_2s_extracted_surface.vtu square_1e2_axi_ts_2_t_2.000000.vtu heat_flux heat_flux 1.7e-5 1e-5
+    NAME 2D_HeatConduction_axi
+    PATH Parabolic/T/2D_axially_symmetric
+    EXECUTABLE ogs
+    EXECUTABLE_ARGS square_1e2_axi.prj
+    TESTER vtkdiff
+    DIFF_DATA
+    square_1e2_axi_ts_10_t_1.000000.vtu square_1e2_axi_ts_10_t_1.000000.vtu temperature temperature 2e-15 0
+    square_1e2_axi_ts_10_t_1.000000.vtu square_1e2_axi_ts_10_t_1.000000.vtu heat_flux heat_flux 1e-14 0
+    REQUIREMENTS NOT OGS_USE_MPI
+)
+# WEDGE 1x1 HEAT CONDUCTION TEST -- same setup as above test but in cartesian coordinates
+AddTest(
+    NAME 2D_HeatConduction_wedge
+    PATH Parabolic/T/2D_axially_symmetric
+    EXECUTABLE ogs
+    EXECUTABLE_ARGS wedge_1e2_axi_ang_0.02.prj
+    TESTER vtkdiff
+    DIFF_DATA
+    wedge_ang_0.02_ts_10_t_1.000000.vtu wedge_ang_0.02_ts_10_t_1.000000.vtu temperature temperature 2e-14 0
+    wedge_ang_0.02_ts_10_t_1.000000.vtu wedge_ang_0.02_ts_10_t_1.000000.vtu heat_flux heat_flux 1e-13 0
     REQUIREMENTS NOT OGS_USE_MPI
 )
-# # WEDGE 1x1 HEATCONDUCTION TEST -- computes reference results for the above test
-# AddTest(
-#      NAME 2D_HeatConduction_wedge
-#      PATH Parabolic/T/2D_axially_symmetric
-#      EXECUTABLE ogs
-#      EXECUTABLE_ARGS wedge_1e2_axi_ang_0.02.prj
-# )
 
 # The 25 BHE array benchmark
 # test results are compared to 2D simulation result

ProcessLib/HydroMechanics/Tests.cmake

@@ -277,7 +277,7 @@ AddTest(
     REQUIREMENTS NOT OGS_USE_MPI
     DIFF_DATA
     expected_square_1e2_UC_late_ts_10_t_1000.000000.vtu square_1e2_UC_late_ts_10_t_1000.000000.vtu displacement displacement 1e-13 1e-16
-    expected_square_1e2_UC_late_ts_10_t_1000.000000.vtu square_1e2_UC_late_ts_10_t_1000.000000.vtu pressure pressure 1e-13 1e-16
+    expected_square_1e2_UC_late_ts_10_t_1000.000000.vtu square_1e2_UC_late_ts_10_t_1000.000000.vtu pressure pressure 2e-13 1e-16
 )
 
 AddTest(

ProcessLib/SteadyStateDiffusion/Tests.cmake

@@ -336,8 +336,9 @@ AddTest(
     wedge_1x1x1_1e3_prism_complete_surface_specific_flux_t_1.000000.vtu wedge_1e3_surfaceflux_wedge_1x1x1_1e3_prism_complete_surface_ts_1_t_1.000000.vtu specific_flux specific_flux 2e-14 0
 )
 
-# SQUARE 1x1 GROUNDWATER FLOW TEST -- AXIALLY SYMMETRIC
-# test results are compared to 3D simulation on a wedge-shaped domain
+# SQUARE 1x1 GROUNDWATER FLOW TEST -- AXIALLY SYMMETRIC, 1e2
+# The results were compared to an analytical solution (method of manufactured
+# solutions). The vtkdiff comparison is against the numerical solution.
 AddTest(
     NAME SteadyStateDiffusion_square_1x1_1e2_axi
     PATH Elliptic/square_1x1_SteadyStateDiffusion
@@ -346,18 +347,23 @@ AddTest(
     TESTER vtkdiff
     REQUIREMENTS NOT OGS_USE_MPI
     DIFF_DATA
-    wedge-1e2-ang-0.02-surface.vtu square_1e2_axi_ts_1_t_1.000000.vtu temperature temperature 1.6e-5 1e-5
+    square_1e2_axi_ts_1_t_1.000000.vtu square_1e2_axi_ts_1_t_1.000000.vtu temperature temperature 2e-15 0
+)
+# WEDGE 1x1 GROUNDWATER FLOW TEST -- same setup as above test but in cartesian coordinates
+AddTest(
+    NAME SteadyStateDiffusion_wedge_1e2_ang_0.02
+    PATH Elliptic/square_1x1_SteadyStateDiffusion
+    EXECUTABLE ogs
+    EXECUTABLE_ARGS wedge_1e2_axi_ang_0.02.prj
+    TESTER vtkdiff
+    REQUIREMENTS NOT OGS_USE_MPI
+    DIFF_DATA
+    wedge_1e2_ang_0.02_ts_1_t_1.000000.vtu wedge_1e2_ang_0.02_ts_1_t_1.000000.vtu temperature temperature 2e-14 0
 )
-# # WEDGE 1x1 GROUNDWATER FLOW TEST -- computes reference results for the above test
-# AddTest(
-#     NAME SteadyStateDiffusion_wedge_1e2_ang_0.02
-#     PATH Elliptic/square_1x1_SteadyStateDiffusion
-#     EXECUTABLE ogs
-#     EXECUTABLE_ARGS wedge_1e2_axi_ang_0.02.prj
-# )
 
-# SQUARE 1x1 GROUNDWATER FLOW TEST -- AXIALLY SYMMETRIC
-# test results are compared to 3D simulation on a wedge-shaped domain
+# SQUARE 1x1 GROUNDWATER FLOW TEST -- AXIALLY SYMMETRIC, 1e4
+# The results were compared to an analytical solution (method of manufactured
+# solutions). The vtkdiff comparison is against the numerical solution.
 AddTest(
     NAME SteadyStateDiffusion_square_1x1_1e4_axi_ang_0.02
     PATH Elliptic/square_1x1_SteadyStateDiffusion
@@ -366,15 +372,19 @@ AddTest(
     TESTER vtkdiff
     REQUIREMENTS NOT OGS_USE_MPI
     DIFF_DATA
-    wedge-1e4-ang-0.02-surface.vtu square_1e4_axi_ts_1_t_1.000000.vtu temperature temperature 1.6e-5 1e-5
+    square_1e4_axi_ts_1_t_1.000000.vtu square_1e4_axi_ts_1_t_1.000000.vtu temperature temperature 2e-14 0
+)
+# WEDGE 1x1 GROUNDWATER FLOW TEST -- same setup as above test but in cartesian coordinates
+AddTest(
+    NAME SteadyStateDiffusion_wedge_1e4_ang_0.02
+    PATH Elliptic/square_1x1_SteadyStateDiffusion
+    EXECUTABLE ogs
+    EXECUTABLE_ARGS wedge_1e4_axi_ang_0.02.prj
+    TESTER vtkdiff
+    REQUIREMENTS NOT OGS_USE_MPI
+    DIFF_DATA
+    wedge_1e4_axi_ang_0.02_ts_1_t_1.000000.vtu wedge_1e4_axi_ang_0.02_ts_1_t_1.000000.vtu temperature temperature 2e-14 0
 )
-# # WEDGE 1x1 GROUNDWATER FLOW TEST -- computes reference results for the above test
-# AddTest(
-#     NAME SteadyStateDiffusion_wedge_1e4_ang_0.02
-#     PATH Elliptic/square_1x1_SteadyStateDiffusion
-#     EXECUTABLE ogs
-#     EXECUTABLE_ARGS wedge_1e4_axi_ang_0.02.prj
-# )
 
 # MPI groundwater flow tests
 AddTest(

ProcessLib/TES/Tests.cmake

@@ -44,13 +44,20 @@ AddTest(
     inert-wedge-extracted-surface-t-1s.vtu tes_inert_axi_ts_4_t_1.000000.vtu temperature temperature 1e-12 2e-9
     inert-wedge-extracted-surface-t-1s.vtu tes_inert_axi_ts_4_t_1.000000.vtu v_mass_frac v_mass_frac 1e-12 2e-9
 )
-# # WEDGE 1x1 TES TEST -- computes reference results for the above test
-# AddTest(
-#     NAME TES_inert_wedge
-#     PATH Parabolic/TES/2D
-#     EXECUTABLE ogs
-#     EXECUTABLE_ARGS tes-inert-wedge.prj
-# )
+# WEDGE 1x1 TES TEST -- computes reference results for the above test
+AddTest(
+    NAME TES_inert_wedge
+    PATH Parabolic/TES/2D
+    EXECUTABLE ogs
+    EXECUTABLE_ARGS tes-inert-wedge.prj
+    TESTER vtkdiff
+    RUNTIME 90
+    REQUIREMENTS NOT OGS_USE_MPI
+    DIFF_DATA
+    tes_inert_wedge_ts_4_t_1.000000.vtu tes_inert_wedge_ts_4_t_1.000000.vtu pressure pressure 1e-12 2e-9
+    tes_inert_wedge_ts_4_t_1.000000.vtu tes_inert_wedge_ts_4_t_1.000000.vtu temperature temperature 1e-12 2e-9
+    tes_inert_wedge_ts_4_t_1.000000.vtu tes_inert_wedge_ts_4_t_1.000000.vtu v_mass_frac v_mass_frac 1e-12 2e-9
+)
 
 # For PETSc/MPI
 AddTest(

ProcessLib/Utils/SetOrGetIntegrationPointData.h

@@ -16,7 +16,7 @@
 
 #include "BaseLib/DynamicSpan.h"
 #include "MathLib/KelvinVector.h"
-#include "MathLib/LinAlg/Eigen/EigenMapTools.h"
+#include "TransposeInPlace.h"
 
 namespace ProcessLib
 {
@@ -65,17 +65,25 @@ std::vector<double> const& getIntegrationPointKelvinVectorData(
     return cache;
 }
 
+//! Overload without \c cache argument.
+//!
+//! \note This function returns the data in transposed storage order compared to
+//! the overloads that have a \c cache argument.
 template <int DisplacementDim, typename IntegrationPointDataVector,
           typename MemberType>
 std::vector<double> getIntegrationPointKelvinVectorData(
     IntegrationPointDataVector const& ip_data_vector, MemberType member)
 {
-    std::vector<double> ip_kelvin_vector_values;
-
-    getIntegrationPointKelvinVectorData<DisplacementDim>(
-        ip_data_vector, member, ip_kelvin_vector_values);
+    constexpr int kelvin_vector_size =
+        MathLib::KelvinVector::kelvin_vector_dimensions(DisplacementDim);
 
-    return ip_kelvin_vector_values;
+    return transposeInPlace<kelvin_vector_size>(
+        [&](std::vector<double>& values)
+        {
+            return getIntegrationPointKelvinVectorData<DisplacementDim>(
+                ip_data_vector, member, values);
+            ;
+        });
 }
 
 template <int DisplacementDim, typename IntegrationPointDataVector,
@@ -207,9 +215,9 @@ std::vector<double> getIntegrationPointDataMaterialStateVariables(
     std::vector<double> result;
     result.reserve(ip_data_vector.size() * n_components);
 
-    for (auto& ip_data_vector : ip_data_vector)
+    for (auto& ip_data : ip_data_vector)
     {
-        auto const values_span = get_values_span(*(ip_data_vector.*member));
+        auto const values_span = get_values_span(*(ip_data.*member));
         assert(values_span.size() == static_cast<std::size_t>(n_components));
 
         result.insert(end(result), values_span.begin(), values_span.end());
@@ -230,7 +238,7 @@ std::size_t setIntegrationPointDataMaterialStateVariables(
     auto const n_integration_points = ip_data_vector.size();
 
     std::size_t position = 0;
-    for (auto& ip_data : ip_data_vector)
+    for (auto const& ip_data : ip_data_vector)
     {
         auto const values_span = get_values_span(*(ip_data.*member));
         std::copy_n(values + position, values_span.size(), values_span.begin());

Tests/Data/Elliptic/square_1x1_SteadyStateDiffusion/square_1e2_axi.prj

@@ -85,14 +85,14 @@
     </linear_solvers>
     <parameters>
         <parameter>
-            <name>T0</name>
-            <type>Constant</type>
-            <value>0</value>
+            <name>solution</name>
+            <type>Function</type>
+            <expression>sin(2*pi*y) * x^2</expression>
         </parameter>
         <parameter>
-            <name>heat_flux_bottom</name>
-            <type>Constant</type>
-            <value>1</value>
+            <name>dsolution_dy</name>
+            <type>Function</type>
+            <expression>-2*pi * cos(2*pi*y) * x^2</expression>
         </parameter>
         <parameter>
             <name>heat_transfer_coefficient</name>
@@ -101,8 +101,13 @@
         </parameter>
         <parameter>
             <name>ambient_temperature</name>
-            <type>Constant</type>
-            <value>0</value>
+            <type>Function</type>
+            <expression>3 * sin(2*pi*y)</expression>
+        </parameter>
+        <parameter>
+            <name>source_term</name>
+            <type>Function</type>
+            <expression>4 * sin(2*pi*y) * (pi^2 * x^2 - 1)</expression>
         </parameter>
     </parameters>
     <process_variables>
@@ -110,13 +115,13 @@
             <name>temperature</name>
             <components>1</components>
             <order>1</order>
-            <initial_condition>T0</initial_condition>
+            <initial_condition>solution</initial_condition>
             <boundary_conditions>
                 <boundary_condition>
                     <geometrical_set>geometry</geometrical_set>
                     <geometry>bottom</geometry>
                     <type>Neumann</type>
-                    <parameter>heat_flux_bottom</parameter>
+                    <parameter>dsolution_dy</parameter>
                 </boundary_condition>
                 <boundary_condition>
                     <geometrical_set>geometry</geometrical_set>
@@ -132,6 +137,13 @@
                     <u_0>ambient_temperature</u_0>
                 </boundary_condition>
             </boundary_conditions>
+            <source_terms>
+                <source_term>
+                    <mesh>square_1x1_quad_1e2</mesh>
+                    <type>Volumetric</type>
+                    <parameter>source_term</parameter>
+                </source_term>
+            </source_terms>
         </process_variable>
     </process_variables>
 </OpenGeoSysProject>

Tests/Data/Elliptic/square_1x1_SteadyStateDiffusion/square_1e2_axi_ts_1_t_1.000000.vtu

+<?xml version="1.0"?>
+<VTKFile type="UnstructuredGrid" version="1.0" byte_order="LittleEndian" header_type="UInt64" compressor="vtkZLibDataCompressor">
+  <UnstructuredGrid>
+    <FieldData>
+      <DataArray type="Int8" Name="OGS_VERSION" NumberOfTuples="27" format="appended" RangeMin="45"                   RangeMax="121"                  offset="0"                   />
+    </FieldData>
+    <Piece NumberOfPoints="121"                  NumberOfCells="100"                 >
+      <PointData>
+        <DataArray type="Float64" Name="D1_left_bottom_N1_right" format="appended" RangeMin="1"                    RangeMax="1.6753144833"         offset="92"                  />
+        <DataArray type="Float64" Name="Linear_1_to_minus1" format="appended" RangeMin="-1"                   RangeMax="1"                    offset="1236"                />
+        <DataArray type="UInt64" Name="bulk_node_ids" format="appended" RangeMin="0"                    RangeMax="120"                  offset="1364"                />
+        <DataArray type="Float64" Name="temperature" format="appended" RangeMin="-0.9512008155"        RangeMax="0.93724397272"        offset="1676"                />
+        <DataArray type="Float64" Name="v" NumberOfComponents="2" format="appended" RangeMin="0.0008661429344"      RangeMax="5.8792463601"         offset="2964"                />
+      </PointData>
+      <CellData>
+        <DataArray type="Int32" Name="MaterialIDs" format="appended" RangeMin="0"                    RangeMax="0"                    offset="5508"                />
+        <DataArray type="UInt64" Name="bulk_element_ids" format="appended" RangeMin="0"                    RangeMax="99"                   offset="5572"                />
+      </CellData>
+      <Points>
+        <DataArray type="Float64" Name="Points" NumberOfComponents="3" format="appended" RangeMin="0"                    RangeMax="1.4142135624"         offset="5852"                />
+      </Points>
+      <Cells>
+        <DataArray type="Int64" Name="connectivity" format="appended" RangeMin=""                     RangeMax=""                     offset="6388"                />
+        <DataArray type="Int64" Name="offsets" format="appended" RangeMin=""                     RangeMax=""                     offset="7112"                />
+        <DataArray type="UInt8" Name="types" format="appended" RangeMin=""                     RangeMax=""                     offset="7420"                />
+      </Cells>
+    </Piece>
+  </UnstructuredGrid>
+  <AppendedData encoding="base64">
+   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+  </AppendedData>
+</VTKFile>

Tests/Data/Elliptic/square_1x1_SteadyStateDiffusion/square_1e4_axi.prj

@@ -85,14 +85,14 @@
     </linear_solvers>
     <parameters>
         <parameter>
-            <name>T0</name>
-            <type>Constant</type>
-            <value>0</value>
+            <name>solution</name>
+            <type>Function</type>
+            <expression>sin(2*pi*y) * x^2</expression>
         </parameter>
         <parameter>
-            <name>heat_flux_bottom</name>
-            <type>Constant</type>
-            <value>1</value>
+            <name>dsolution_dy</name>
+            <type>Function</type>
+            <expression>-2*pi * cos(2*pi*y) * x^2</expression>
         </parameter>
         <parameter>
             <name>heat_transfer_coefficient</name>
@@ -101,8 +101,13 @@
         </parameter>
         <parameter>
             <name>ambient_temperature</name>
-            <type>Constant</type>
-            <value>0</value>
+            <type>Function</type>
+            <expression>3 * sin(2*pi*y)</expression>
+        </parameter>
+        <parameter>
+            <name>source_term</name>
+            <type>Function</type>
+            <expression>4 * sin(2*pi*y) * (pi^2 * x^2 - 1)</expression>
         </parameter>
     </parameters>
     <process_variables>
@@ -110,13 +115,13 @@
             <name>temperature</name>
             <components>1</components>
             <order>1</order>
-            <initial_condition>T0</initial_condition>
+            <initial_condition>solution</initial_condition>
             <boundary_conditions>
                 <boundary_condition>
                     <geometrical_set>geometry</geometrical_set>
                     <geometry>bottom</geometry>
                     <type>Neumann</type>
-                    <parameter>heat_flux_bottom</parameter>
+                    <parameter>dsolution_dy</parameter>
                 </boundary_condition>
                 <boundary_condition>
                     <geometrical_set>geometry</geometrical_set>
@@ -132,6 +137,13 @@
                     <u_0>ambient_temperature</u_0>
                 </boundary_condition>
             </boundary_conditions>
+            <source_terms>
+                <source_term>
+                    <mesh>square_1x1_quad_1e4</mesh>
+                    <type>Volumetric</type>
+                    <parameter>source_term</parameter>
+                </source_term>
+            </source_terms>
         </process_variable>
     </process_variables>
 </OpenGeoSysProject>

Tests/Data/Elliptic/square_1x1_SteadyStateDiffusion/wedge-1e2-ang-0.02-surface.vtu

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-        <DataArray type="Float64" Name="v_x" format="binary" RangeMin="0" RangeMax="0">
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-        <DataArray type="Int32" Name="MaterialIDs" format="binary" RangeMin="0" RangeMax="0">
-          AQAAAAAAAAAAgAAAAAAAAOQBAAAAAAAADgAAAAAAAAA=eJxjYBgFwx0AAAHkAAE=
-        </DataArray>
-        <DataArray type="Int8" Name="vtkValidPointMask" format="binary" RangeMin="1" RangeMax="1">
-          AQAAAAAAAAAAgAAAAAAAAHkAAAAAAAAADAAAAAAAAAA=eJxjZBwgAAAdTgB6
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-      </PointData>
-      <CellData>
-      </CellData>
-      <Points>
-        <DataArray type="Float64" Name="Points" NumberOfComponents="3" format="binary" RangeMin="0" RangeMax="1.4142135624">
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-      </Points>
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Tests/Data/Elliptic/square_1x1_SteadyStateDiffusion/wedge-1e2-ang-0.2-surface.vtu

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